A new study in the journal Environmental Science & Technology looked at governmental food testing in Japan. The study reviewed foods testing for cesium 137 contamination and also strontium 90 contamination. Official assumptions had been than there was a set ratio of cesium 137 to strontium 90 across all foods. What was found is that over time the ratio of strontium 90 in foods had increased. This makes the standard assumed ratio being used incorrect. This could lead to underestimates of the risk from contaminated foods on human health. This is even more problematic as testing for actual strontium 90 in foods is done less often due to the complexity of the testing method.